Monday, March 02, 2009

There was a solar eclipse earlier this month — but it wasn't visible anywhere on Earth.

Rather, a Japanese space probe in orbit around the moon got spectacular high-definition video of the sun being blocked — by the Earth, producing an otherworldly "diamond-ring" eclipse.

It may be only the third time such an eclipse has been viewed by terrestrials, human or otherwise.

An American lunar lander got a blurry snapshot of a solar eclipse in 1967, and two years later Apollo 12 astronauts got treated to the same thing on their way back from the moon.

The Kaguya, or Selene, probe was traveling from the dark to the light side of the moon on Feb. 9.

The sun rose over the moon's surface, as usual, but on Feb. 9 it was just a thin ring surrounding darkness.

(The Earth's disk is a bit smaller than the sun's when viewed from the moon; on Earth, the moon just about covers the sun.)

In the video, only a small semi-circle is visible at first as the sun rises over the horizon. The circle quickly expands, but before it's complete the sun suddenly breaks forth from the lower right corner of the circle, filling the screen with light.